1. Field of the Invention
The present invention relates to an apparatus for recording information, such as audio (sound/voice) signals and video (image) signals, on a recording medium and reproducing the information from the recording medium, wherein the recording medium has a ring buffer region in which overwriting takes place repeatedly.
2. Description of the Related Art
A hard disc and a hard disc recorder are receiving increased attention because the hard disc recorder and hard disc can replace a video tape recorder and video tape as an apparatus for recording television programs. When a hard disc is used as a recording medium, so-called time shift reproduction becomes possible which reproduces a recorded program while recording a currently broadcast program. In order to achieve the time shift reproduction function, the hard disc has a ring buffer region.
Referring to FIG. 1 of the accompanying drawings, recordation and reproduction of information within the ring buffer region during the time shift reproduction will be described.
In FIG. 1, a write position WP indicates a current recording position in the ring buffer region, and a read position RP indicates a current reproducing position in the ring buffer region. The positions WP and RP gradually move independently from the front end of the ring buffer region to the rear end of the ring buffer region as indicated by the unshaded arrows. While the positions WP and RP are moving, a recordation/reproduction head (not shown) provided in a hard disc recorder alternately executes a reading operation to retrieve recorded information from the read position RP and a recording operation to record information at the write position WP. When the write position WP (or the read position RP) reaches the rear end of the ring buffer region, the write position WP (or the read position RP) returns to the front end of the ring buffer region. In other words, track jumping of the recordation/reproduction head from the rear end of the buffer ring region to the front end of the buffer ring region occurs as indicated by the broken line. After the track jumping, the write position WP and read position RP start moving again towards the rear end of the ring buffer region independently. The recordation/reproduction head alternately performs the information reading operation and the information recording operation again as the recordation/reproduction head moves towards the rear end of the ring buffer region.
As described above, continuous recording and reproducing of the information takes place repeatedly in a continuous or circulating manner in the ring buffer region. In order to ensure continuousness of the recordation and reproduction even while the recordation/reproduction head is jumping from the rear end of the ring buffer region to the front end as indicated by the broken line (i.e., during the track jumping of the head), there is provided a track buffer in the hard disc recorder which is a buffer used for recording and reproducing information during the track jumping. During the track jumping, the recordation/reproduction head cannot record or reproduce information on or from the hard disc. In other words, the recordation/reproduction head cannot access the hard disc during the track jumping. The track buffer is provided for compensating for information discontinuity caused by the track jumping.
When the ring buffer region is large, the time for the track jumping of the recordation/reproduction head is correspondingly large as understood from FIG. 1. Consequently, the track buffer is required to have a large capacity to compensate for the absence or non-availability of the recordation/reproduction head during the track jumping.
An object of the present invention is to provide an information recording and reproducing apparatus that can include a ring buffer region having a large capacity without causing the above described problem.
Another object of the present invention is to provide an information recording and reproducing method that can provide a ring buffer region having a large capacity without causing the above described problem.
According to one aspect of the present invention, there is provided an information recording and reproducing method for recording and reproducing a signal in and from a ring buffer region of a recording medium with a recording/reproducing head, the ring buffer region being divided into a plurality of ring regions, the information recording and reproducing method comprising the step of recording or reproducing the signal in and from the plurality of ring regions of the ring buffer region from one end (first end) of the ring buffer region towards the other end (second end) of the ring buffer region by skipping over at least one ring region at a time, and the step of recording or reproducing the signal in and from those ring regions of the ring buffer region which are skipped over in the preceding step from the other end of the ring buffer region towards the one end of the ring buffer region. The recording/reproducing head does not jump the entire length of the ring buffer region since the ring buffer region is divided into smaller regions. Therefore, a jumping distance of the recording/reproducing head is reduced, and a buffer required for compensating for discontinuity caused by track jumping of the recording/reproducing head can have a smaller capacity. Accordingly, the size of the ring buffer region can be maintained while reducing the recording capacity of the buffer.
According to another aspect of the present invention, there is provided an information recording and reproducing apparatus for recording and reproducing a signal in and from a ring buffer region of a recording medium, the ring buffer region being divided into a plurality of ring regions, said apparatus comprising a recording and reproducing head for recording or reproducing the signal in or from the plurality of ring regions, a memory for storing a predetermined order, and a movement mechanism for moving the recording and reproducing head in accordance with the predetermined order. The predetermined order includes skipping over at least one ring region at a time.